Hmmm, I don't really see a reason to release the source files... I'll consider it, but there is a lot of work going into these and I'm not sure I would want everyone to have the ability to just change it.
In the case for the sun, I can't really render in passes because the layers are dependent on each other for animation. But now that I have the look I want, animation will be easy since it is about motion and not position. I can animate at quarter resolution or less to make my job easier.
I'm going to work a little on the colors for the sun, but I don't think it will change too drastically. I like that the new one looks like it has life. It looks hot and full of energy, where as the old one looks like a marble with effects. (IMO)
Also, screens of EndGame coming probably, tomorrow or Tuesday.